Ankylosing Spondylitis

Definition/Description

Ankylosing spondylitis (also called Bechterew's disease) is a spondyloarthritis of the spine and pelvis. It is a common chronic inflammatory rheumatic disease with unknown etiology. AS is associated with the HLA-B27 antigen and also with other chronic inflammatory diseases. AS affects the axial skeleton and sacroiliac joints, causing characteristic inflammatory back pain, which can lead to structural and functional impairments and a decrease in quality of life.[1][2][3][4][5] Affected joints progressively become stiff and sensitive due to a bone formation at the level of the joint capsule and cartilage. It causes a decreased range of motion and gives the spine an appearance similar to bamboo, hence the alternative name "bamboo spine".
Although not often recognised, ankylosing spondylitis can also cause peripheral joint pain, particularly in the hips, knees, ankles, and shoulders and neck.[6] It involves synovial and cartilaginous joints, as well as sites of tendon and ligamentous attachment.[3][5]Early diagnosis and treatment helps to control the pain and stiffness and may reduce or prevent significant deformity.

Clinically Relevant Anatomy

Pain in AS can be caused by sacroiliitis, enthesitis and spondylitis.[2] Initially the sacroiliac joints, situated in the lumbar part of the back, which connect the spine and the pelvis, are damaged. Subsequently the inflammation moves to entheses, where ligaments and tendons integrate into bone.[6] Eventually, the spine is affected by this inflammation. The vertebral column normally exists of 24 vertebrae, joined together by ligaments and separated by intervertebral discs.
Patients diagnosed with AS form calcium deposits in the ligaments between and around the intervertebral discs. An accumulation of the deposits leads to ossification [3], starting from the vertebral rim towards the annulus fibrosis and characterised by syndesmophytes.[4] In highly advanced cases, the spine can fuse together as a result of the bone formation.


Axial Skeleton
Sacroiliac Joint


Epidemiology /Etiology

AS Affects 0.1 to 0.2% of the population and [7] is predominantly seen in males in a 3:1 ratio. The onset of symptoms generally occurs in late adolescent years to early adulthood. The peak age in which AS manifests varies from the teens to the fourth decade of life.[7] Its prevalence is highest among white people (0.1-0.2%), less common in American blacks and rare among Japanese, so there is both a familial and a racial predisposition to this disease.[5]
The etiology of AS is not fully understood, although a strong genetic link has been determined.[5] In addition, a direct relationship between AS and the major histocompatibility human leukocyte antigen (HLA)-B27 has also been determined.[8] The exact role of this antigen is unknown, but is believed to act as a receptor for an inciting antigen leading to AS. HLA-B27 occurs in 90-95% of patients with ankylosing spondylitis, compared to a 6 to 9% incidence in the normal population. [5]

The majority of patients are HLA-B27 positive and the risk passing the same antigen onto a child is 1 in 2, [6] so ankylosing spondylitis is a common, highly heritable inflammatory arthritis. [8] Environmental or bacterial factors can also be a trigger. [6] 
Initially, there is an infiltration of the subchondral bone by granulation tissue which causes small lesions, ultimately leading to joint erosion (the adjacent cartilage is distorted which produces a very irregular surface).[5] These lesions in the annulus eventually undergo ossification, leading to a fusion effect of the spinal segments and the similarity in appearance to bamboo. In the spine this occurs at the junction of the vertebrae and the annular fibres of the intervertebral disc.
When synovium is the affected tissue, there is an infiltration by macrophages and lymphocytes. This is followed by replacement of the cartilage or fibrous tissue by a scar like fibroblast invasion which rapidly ossifies. The inflammatory response in the bone adjacent to the involved fibrocartilage, ligament or periosteum is frequently quite severe. As of the spine can resemble an infectious discitis when the spine is initially involved and can be an additional source of confusion for the treating therapist. [5]

Ankylosing Process
"Bamboo Spine" on X-ray

Characteristics/Clinical Presentation

The clinical presentation is usually an insidious onset of back pain in the sacroiliac (SI) joints and gluteal regions and progresses to involve the entire spine. [7] Morning stiffness lasting greater than 30 minutes is a common subjective complaint, as well as waking up in the second half of the night. Pain and stiffness increase with inactivity and improve with exercise.[5] It may also variably involve peripheral joints, eyes, skin, and the cardiac and intestinal systems. [7] Eye disease occurs in about 25% of the patients as either iridocyclitis or conjunctivitis. [5] Joints other than those of the axial skeleton can be involved with an inflammatory arthritis and synovitis which is seldom as destructive as that of rheumatoid arthritis. The hips, shoulder and knees are the most commonly and most severely affected of the extremity joints. [5] Complaints of intermittent breathing difficulties may also be a common complaint because AS may cause a decrease in chest expansion.

Differential Diagnosis

Common disorders to consider as differential diagnoses with AS are:
• Degenerative Disc Disease
• Herniated Intervertebral Disc
• Fractures and/or dislocation
• Osteoarthritis
• Spinal Stenosis
• Spondylolisthesis, Spondylolysis, and Spondylosis
• Reactive arthritis
• Inflammatory bowel-related arthritis
• Diffuse idiopathic skeletal hyperostosis (DISH)
• Rheumatoid arthritis [7]
• Psoriatic arthritis [7]
• Reiter syndrome (milder with asymmetric sacroiliitis) [7]

Diagnostic Procedures

The diagnosis of AS is commonly made through a combination of thorough subjective and physical examinations, laboratory data and imaging studies. Common laboratory data include blood tests to determine the presence of the HLA-B2 antigen or substances that indicate an inflammatory process: [9]

  • Erythrocyte sedimentation rate (ESR): This is a blood test for inflammation, in approximately one third of the SA patients there is a raised ESR observable in exacerbations of the disease, but other conditions can also cause a high ESR.[4] [9]
  • C-reactive proteins (CRP): This is also a marker of inflammation and is found in 50-70% [9] of people with AS.[9] However, this test is discouraged because it is associated with a high rate of false positives due to the fact that high CRP occurs in 10% of the Caucasian population.[7]
  • HLA-B27 antigen: HLA B27 is positive in 80-90% of AS patients, more so in the white population and than in some other ethnic groups, especially African Americans. [2] The presence of this hereditary factor is not required for a diagnosis of AS and it does not absolutely confirm or exclude the presence of this disease. The HLA-B27 antigen also occurs in other inflammatory conditions of the joints or intestines. [9]

Laboratory tests are specific and are often more helpful to exclude other diagnoses rather than confirming AS. In combination with other symptoms, the diagnosis can often be made more accurate. [2][4]

Detection of AS by medical imaging [9]

  • X-rays are the most useful imaging modality in established the disease, although they may be normal in the early phases. X-ray shows up areas where the bone has been worn away by the condition. The vertebrae of the spine may start to fuse together because the ligaments between them become calcified.
  • MRI scanning may also be useful in identifying early sacroiliitis. MRI of the sacroiliac joints is more sensitive than either plain X-ray or CT scan in demonstrating sacroiliitis. Sacroiliitis initially shows as blurring in the lower part of the joint, then bony erosions or sclerosis occur and widening or eventual fusion of the joint.


Radiographic findings are graded on a scale of 0 to 4 where 0 represents normal findings and 4 represents complete ankylosis.[2] A definitive diagnosis is considered with the following combinations:

  • Grade 3 or 4 at bilateral SI joints on radiograph with at least one physical finding
  • Grade 3 or 4 unilaterally (or Grade 2 bilaterally) with two physical findings

Standard questionnaires can also be used as part of the assessment to build a picture of the evolution of the disease.[1] Available questionnaires include:

  • AMOR criteria for Spondyloarthritis
  • BASDAI index ( Bath Ankylosing Spondylitis Disease Activity Index)
  • BASDMI (Bath Ankylosing spondylitis Metrology Index)
  • BASFI index ( Bath Ankylosing Spondylitis Functional Index)
  • BAS-G index ( Bath Ankylosing Spondylitis Global Index)


The modified New York criteria (1984) for diagnosing AS combines physical findings with radiograph studies:
Clinical criteria

  • Low back pain and stiffness for at least 3 months, which improves with exercise, but is not relieved by rest
  • Limited lumbar spinal motion in sagittal (sideways) and frontal (forward and backward) planes
  • Chest expansion decreased relative to normal values corrected for age and sex


Radiologic criteria

  • Bilateral sacroiliitis grade 2 to 4
  • Unilateral sacroiliitis grade 3 or 4


Grading

  • A patient can be classified as having definite AS if at least 1 clinical criterion (inflammatory back pain, limitation of mobility of the lumbar spine, or limitation of chest expansion) plus the radiologic criterion (radiographic sacroiliitis of grade 2 bilaterally or grade 3–4 unilaterally) are fulfilled.
  • A probable diagnosis of AS is made if three clinical criteria are present or the radiologic criterion is present without any signs or symptoms satisfying the clinical criteria [6]

Outcome Measures

Certain quality of life or global rating of change outcome measures may be most appropriate in the physical therapy setting because AS often affects the patient on a more general level. However, since AS affects the spine, outcome measures such as the

may also be appropriate. Laboratory values, such as the CRP, are used to monitor the effectiveness of medication treatments.

Examination

A thorough physical examination, particularly of the musculoskeletal system, is needed. Clinical signs are sometimes minimal in the early stages of the disease. Examination of the sacroiliac joints and the spine (including the neck), measurement of chest expansion and range of motion of the hip and shoulder joints, and a search for signs of enthesitis are critical in making an early diagnosis of AS. [5][10][2]

Video 1: The aim of the Schober test is to assess the mobility of the lumbar spine, which can be abnormal even when it is not obvious to the individual.

[11]

Video 2: The lumbar spine side flexion test is another test to measure the lumbar spine mobility.

[12]

Video 3: When ankylosing spondylitis affects the mid-back region, normal chest expansion may be compromised. The aim of the chest expansion test is to assess the thoracic mobility.

[13]

Video 4: The tragus to wall test is a test to measure the cervical mobility.

Medical Management

First line drug treatment : NSAIDs
Non-steroidal anti-inflammatory drugs are primarily used for ankylosing spondylitis (AS) patients to reduce the inflammatory symptoms such as pain and stiffness of the spine and other joints. It is important to remember that NSAIDs do not alter the disease cause and only affects the symptoms.[3] Commonly used NSAIDs for AS are tolmetin, sulindac, naproxen, diclofenac and indomethacin, [4] which is the most effective.[5]


Second line treatments: corticosteroids and DMARDs
When patients are refractory to NSAIDs, corticosteroid injections may be prescribed or disease modifying anti-rheumatic drugs (DMARDs)[3], including methotrexate and sulfasalazine. However, corticosteroids do not have evidence-based outcomes and DMARDs are only proven to be effective for the treatment of peripheral joint diseases.[5]


Biological medications


Tumor necrosis factor inhibitors
Research has shown that patients with ankylosing spondylitis have an abundance of pro-inflammatory cytokine tumor necrosis factor (TNF) messenger RNA and proteins in the sacroiliac joints. The use of anti-tumor necrosis factor therapies has therefore proven to be positive.[8] [7] Etanercept [10]and Infliximab[7] have both been used to treat AS patients with successful results.


Biphosphonates
Biphosphonates have good outcomes on bone turnover, which is positive as ankylosing spondylitis is characterised by bone resorption and formation. Neridronate and pamidronate are amino-biphosphonates with similar effects as the TNF inhibitor Infliximab. [9]
All drugs have side effects, so patients with other health issues need to verify if they are able to take the recommended medicines.

Physical Therapy Management

Physical therapy is an essential part in the treatment of AS.[3] (LOE:5) It aims to alleviate pain, increase spinal mobility and functional capacity, reduce morning stiffness, correct postural deformities, increase mobility and improve the psychosocial status of the patients.
The Global Postural Reeducation method has shown promising short- and long-term results [4] (LOE:5)and includes specific strengthening and flexibility exercises. A global and functional approach is more efficient than localised exercises in AS patients.[5] (LOE:5)
Group classes with the GPR method appears to result in greater improvement than with home exercises due to mutual encouragement, reciprocal motivation and exchange of experiences within the group environment. The effects of pulmonary function in AS patients may further decrease their psychological state and quality of life in patients, [8] (LOE:3A)so it is important include respiratory exercises within any prgramme, [7] (LOE:5)such as:

  • Twice the normal rate of inspiration through the nose and expiration through the mouth
  • Encourage normal expiration through the nose and normal expiration through the mouth
  • Deep breathing and then expiration through the mouth slowly
  • Resistance exercises for inspiratory pulmonary muscles

A rigorous exercise routine with postural correction can be applied to delay, and possibly stop, the progression of the disease. Spinal extension exercises are the key component and should be done twice daily. Education in self-management is essential to discourage therapist dependence. Young patients need a great deal of encouragement and support as self-worth understandably diminishes with the progression of postural deformity. [6](LOE:5) 

Treatment is essentially to minimize or prevent deformity. These deformities are excessive dorsal kyphosis with compensatory cervical lordosis and hip flexion contracture. Non-Surgical treatment involves:

  • Proper sleeping posture on a solid, flat bed without pillow. Frequent sleeping or lying in prone position.
  • Posture exercises with upper back hyperextension (performed with avoidance of lumbar hyperextension).
  • Breathing exercises to increase or maintain rib cage excursion, as well as instruction in abdominothoracic breathing.
  • Range of motion exercises for hips and knees to prevent flexion limitation and contractures.
  • Periodic rest periods with avoidance of fatigue.
  • Bracing or corseting (combined with exercises). [1](LOE:4)

Manual mobilisation improves chest expansion, posture and spinal mobility.[8] (LOE:3A) Both active angular and passive mobility exercises can be used in the physiological directions of the joints in the spinal column and the chest wall in flexion, extension, lateral flexion and rotation and in different starting positions (lying face down, sideways, on the back and in a sitting position). Passive mobility exercises consist of general, angular movements and specific translatory movements.
In addition to conventional exercises (flexibility exercises for cervical, thoracic and lumbar spine and major muscle groups) and respiratory exercises (pursed-lip breathing, expiratory abdomen augmentation, and synchronisation of thoracic and abdominal movement), aerobic exercises such as swimming and walking are recommended. Research has shown a significant increase in chest expansion following swimming programs and a significant increase in PvO2 and Six Minute Walk Test distances in patients practising swimming and/or walking aerobic exercises. [8] (LOE:3A)Aerobic exercises lead to a bigger chest expansion and therefore a better functional capacity and also decrease the chances of respiratory failure.
Spa therapy has shown significant positive short- and long-term effects on pain, stiffness, well-being and functioning of patients with AS.[9] (LOE:1A)However, this treatment is very expensive and since the optimal length of therapy is four weeks, this is unfeasible for many people, especially those who are in the workforce or have families at home.
Results of different studies shows us that an individual home-based or supervised exercise program is better than no intervention. Supervised group physiotherapy is better than home exercises and combined inpatient spa-exercise therapy followed by group physiotherapy is better than group physiotherapy alone. [9](LOE:1A)

Exercise Type Methods Recommended Dosage Effects on Pulmonary Function
General Exercises See Table 2 below for recommended exercises to include in the exercise program[14](LOE:1B) 2 Times Per Week Minimum, For 6 Months Increased Functional Capacity, Improved Chest Expansion.
Pilates[15](LOE:1B)  Consists of a supervised Pilates session. The difficulty of the movements should be easy to moderate. Difficulty not to exceed 14 on the BORG scale. 1 Hour Sessions, 3 Times Per Week, For 12 Weeks Significant Improvements In Chest Expansion.
Incentive Spirometry[16](LOE:1B) This is a session of breath holding and controlling breaths. Patients should carry out 3-5 second breath holds and carry out Forced Expiratory Techniques interspersed between breath holds. This treatment should be combined with General Exercises and should not be used as a sole treatment (see above for general exercises 30 Minute Sessions, Once Per Day, For 16 Weeks Improved Chest Expansion and Improved Forced Vital Capacity
Inspiratory Muscle Training[17](LOE:1B) The supervised exercise program, delivered by a qualified physiotherapist, should include; motion and flexibility exercises of the cervical, thoracic, and lumbar spine; stretching of the hamstring muscles, erector spine muscle, and shoulder muscles; control abdominal and diaphragm breathing exercises and chest expansion exercises. In addition to these exercises at home patients should perform six loaded inspirations with a 60 second rest period between each inspiration. This sequence of six exercises continued with 45, 30, 15, 10 and five second rest periods up to 36 loaded inspirations. A rating of more than 17 on the BORG requires the patient to stop exercising. 40 minute session (supervised), Once Per Week, 5 Unsupervised Home Exercise Sessions Per Week Increased Aerobic Capacity, Improved Resting Pulmonary Function and Ventilatory Efficiency.
Manual Mobilisation [18](LOE:1B) Both active angular and passive mobility exercises can be used in the physiological directions of the joints in the spinal column and the chest wall in flexion, extension, lateral flexion and rotation and in different starting positions. Passive mobility exercises consist of general, angular movements and specific translatory movements. 1 Hour Sessions, 2 Times Per Week, for 8 Weeks Improved Chest Expansion, Posture and Spinal Mobility
Aerobic Exercise[19](LOE:5) Research shows that in the short term aerobic exercise has a major effect of all symptoms relating to ankylosing spondylitis. Although there is no bad form of aerobic exercise, studies show that swimming is the best for pulmonary rehabilitation. Studies also show that high impact contact sports should be avoided as this can have a negative impact on symptoms relating to AS 1 hour per day, 5 days per week. (more can be done however should not achieve more than 17 on the BORG Scale Improved Chest Expansion, Improved Functional Capacity and Decreases the Chance of Respiratory Failure.

Table of AS Exs.jpg

Hydrotherapy/Aquatic Physiotherapy

Hydrotherapy is used for many pathology’s relating to back pain.[20](LOE: 2B) The rationale for the use of hydrotherapy in patients with Ankylosing Spondylitis looks at addressing common symptoms such as stiffness and associated back pain, stooped posture and fatigue.

These factors include:

  • Warm water provides a relaxation effect the the tight musculature around the back.
  • Buoyancy of water allows stretching to feel easier than on land.
  • Reduced pain while stretching/exercising as water provides shock absorption.
  • Easier to stay upright as effect of gravity reduced in water.
  • Effort required is reduced due to upward thrust of the water. In waist high water, body weight is half of what it would be on land. [21](LOE:2C)

Evidence for the use of hydrotherapy/aquatic physiotherapy
Dunbar et al looked at the effect of hydrotherapy for patients with AS compared to home-based exercise programs. It concluded that an intensive hydrotherapy programme produced better outcomes in terms of pain and quality of life for AS patients compared to the home exercise group[22] (LOE:1B)and is a popular way to exercise, [23](LOE:4) although physiotherapist led formal hydrotherapy classes are not always easy to access.[24](LOE:1A)

Spa therapy has shown significant positive short- and long-term effects on pain, stiffness, well-being and functioning of patients with AS.[25] (LOE:5)However, this treatment is very expensive and since the optimal length of therapy is four weeks, this is unfeasible for many people financially.

Group Therapy

Group therapy has been reported to be superior to individualised therapy in improving thoracolumbar mobility and aerobic fitness, as well as having an important effect on patient reported global health[26].(LOE:1B) Pilates has also been shown to have many positive effects on AS, most notably on improving physical capacity[27].(LOE:1B) Other studies have noted a relationship between pilates and an improved quality of life particularly in patients who are in the early stages of AS even after a relatively short duration of treatment. While the method is easy to learn and adaptable to individual variations, it can be easily implemented in the rehabilitation treatment of ankylosing spondylitis[28].(LOE:2B)

Mindfulness Based Therapies
Non exercise-based interventions have also been shown to have positive effects in the management of AS such as mindfulness courses using a Vitality Training Program (VTP). In a 6-month follow up session statistically significant improvements were reported in psychological distress (measured by the General Health Questionnaire). Additionally, other improvements were reported in self-efficacy, pain and symptoms, emotional processing, fatigue, self-care ability and overall well-being[29].(LOE:1B)


Due to existing evidence suggesting the effectiveness of mindfulness interventions, scope has been established for its use in a group session in order to manage patient fatigue (which has been further sub-categorised into physical emotional, and psychological components). This is due to patients reporting that they often feel lost without any formal guidance or support and patients have expressed a preference for psychological therapies as opposed to a pharmacological one for managing fatigue. Mindfulness-Based Stress Reduction (MBSR) is a useful resource for self management. [30].(LOE:4)

Clinical Bottom Line

Ankylosing spondyitis is a common chronic inflammatory rheumatic disease with unknow aetiology. Affected joints progressively become stiff and sensitive due to a bone formation at the level of the joint capsule and cartilage. This can lead to structural and functional impairments and a decrease in quality of life. Regions most affected by the disease are the axial skeleton and sacroiliac joints. A combination of medicines (such as non-steroidal anti-inflammatory drugs and biological medications) and physical therapy is recommended. Physiotherapy primarily consists of range of motion and respiratory exercises as well as working on postural corrections.

Presentations

https://http://www.youtube.com/watch?v=hci1ea2coy8Ankylosing spondylitis ppt.PNG
Ankylosing Spondylitis

This presentation, created by Kyle Martin, Robby Martin, Haley Metzner, and Stacey Potter; Texas State DPT Class.

View the presentation


References

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